a) field of the invention
The present invention is concerned with an emergency device for use in a dwelling or any similar place provided with a sump pump in the basement, in order to operate this sump pump and, if desired, to switch on some emergency lights in the case of a failure of the main electric power supply in this dwelling.
b) brief description of the prior art
As is well known, most of the dwellings, especially those located close to a lake or a river, are equipped with a draining unit comprising a sump reservoir, a sump and a water pump which is usually an electrical sump pump. The purpose of the reservoir is to collect rain and waste waters. When the collected water reaches a certain level, it is transferred to a sump, through a pipe, and then pumped out to the sewer by the sump pump.
The problem with such a "flood control system" is that it becomes incoperative in case of electric power failure. However, such failure usually occurs in the case of severe storm and/or river overflowing, i.e. when the sump pump is deeply needed.
To solve this problem, it has already been suggested to use "emergency" devices like those disclosed by way of examples, in U.S. Pat. Nos. 3,726,606 and 3,814,544.
In the first one of these two patents, i.e. U.S. Pat. No. 3,726,606, there is disclosed a sump apparatus comprising two pumps, a first one operated by a principal power source and a second one by a storage battery. A control system is provided to operate the first pump and simultaneously charge the storage battery when the principal power source is operative. The control system is also designed to automatically connect the second pump to the storage battery whenever the principal power source fails or the first pump alone is unable to empty the sump reservoir, in order to activate this second pump and thus makes it use that the sump reservoir is actually emptied. The control system further includes warning means including pilot lights and an ampmeter to indicate when both pumps are simultaneously operating and when there is some failure in the power source or storage battery.
In U.S. Pat. No. 3,814,544, there is disclosed an auxiliary sump pump assembly operated by a storage battery in response to a float switch, which includes an electrical battery charger for maintaining the battery in condition to operate. A control system is also provided, including a battery condition indicator, a charger operating light, a manual test switch and a timer to operating the pump through a test cycle.
Other devices, like the one disclosed, by way of example, in U.S. Pat. No. 3,162,134, have also been proposed in the past, for automatically connecting an emergency battery to the terminals of a pump motor to keep the pump running in the case of a main power failure, all of these devices including a battery charger for maintaining the emergency battery in condition to operate and a warning system to automatically inform the occupant of any misfunctioning.
If the emergency devices of the above mentioned type air efficient to keep a sump pump operative for a short period of time in the case of a major power failure, they are however inoperative over a long period of time. Indeed, they become inoperative as soon as the storage battery (which cannot anymore be recharged by the "charger" because of the power failure) runs down, such a running down being usually quite fast because, in the case of a major storm or overflow, the sump pump has to work almost permanently to prevent the basement of dwelling from being "drowned".